Function Validate

Validate<T = any>(
predicate: (value: any, item: T) => boolean,
message: string,
): PropertyDecorator
Property decorator that attaches a validation rule to the decorated field. The rule is enforced on every EntityRepository.create and EntityRepository.update call.
Type Parameters
- T = any
  The entity class to which this rule belongs.
Parameters
- predicate: (value: any, item: T) => boolean
  A function that returns true when the field value is valid. Receives both the field value and the full entity instance.
- message: string
  A short, human-readable description of the constraint, appended to the thrown error on failure.
Returns PropertyDecorator
Throws
Error - On write operations when any rule's predicate returns false. The error message lists all failing rules in the format field: message, joined by ; .
Example
```
@DataClass()
class User {
  @KeyPath()
  id!: string;

  @Validate((v) => typeof v === 'string' && v.includes('@'), 'must be a valid email')
  email!: string;

  @Validate((v) => typeof v === 'number' && v >= 0, 'age must be >= 0')
  age!: number;
}
```
- Defined in index.ts:1523